A Vision in Red
by Doleesa
Summary: Kara's infected with Red!K, and a trail of destruction is left in her wake.


**A/N: Hello.**

 **This is pure, unadulterated angst and anger and violence; I'm having a rough few weeks mentally and it tends to manifest into this kind of writing. If you're following my Child of Our Golden Sun series, this is so very far away from that. It's not even within the same universe. I adore that series and the amazing response it's gotten, but right now, I needed to take a step back from it.**

 **I was actually lurking through tumblr when I saw the following prompt and saved it so I could maybe write it;**

 **"Red!K fic where Lena does everything in her power to bring Kara back. Kara wakes up at the DEO and when she turns she sees Alex with blood on her hands but it's not hers, it's Lena's who's on the bed beside her." - from saneunderthelamplight on tumblr, so shout out to them and someone link them this (it's not exactly the same as the prompt but eh. And here's the link to the post too post/161158999683/redk-fic-where-lena-does-everything-in-her-power)**

 **Anyway, read on and let me know how you feel about this.**

* * *

It should have been routine- it _was_ routine.

Just another CADMUS attack unleashed on the city.

Just another working day for Supergirl.

And Kara had stopped it, just barely and Lillian and Hank Henshaw had escaped again but Kara had stopped it; dismantled bombs and dispatched alien tech and just generally been Super.

And if she staggers a little when she gets to her feet after the fight, Alex doesn't think much of it as she steadies Kara with an arm around her waist; it _had_ been a brutal fight.

But it can't have been that bad since Kara straightens pretty quickly, and if she shrugs Alex off a little too abruptly then Alex just blames it on Kara's disorientation.

A voice tickles the back of Alex's mind, warning, as she watches Kara take off, and Alex notes her flight is a little shaky though she straightens out in mere moments. Before she gets to dwell on it however, she's being called back to the DEO to deal with a different crisis involving Lord Technologies.

* * *

Maxwell Lord is as obnoxious as ever, and perhaps even slimier.

He won't cooperate, won't tell them what happened beyond the fact that his lab was broken into and claims nothing is missing.

Which wouldn't be a problem the DEO would dwell on – they'd gladly hand over Max to Maggie and the NCPD to be dealt with – if it weren't for the small issue of Maxwell Lord knowing, more or less, everything there is to know about the DEO and Kara's identity. And that small issue of him trying to bring down Supergirl on multiple occasions.

The interrogation lasts for a few hours, in which Alex gets to delight in roughing up Max Lord for at least one of those hours while Winn tries to hack his way into figuring out what Max is hiding before J'onn, sighing and tired, declares to just let the man go.

And that's when they realize something's amiss.

Because there are multiple reports of fires and accidents and robberies, and no Supergirl in sight.

Agent Vasquez informs them that Supergirl has been offline, but her tracker seems to be heading back towards the DEO.

No sooner than Susan Vasquez has finished her sentence does Supergirl land, hard and aggressive and concrete-splitting. Though she grins easily, almost dangerously, and the alarm bells in the back of Alex's mind from earlier are blaring now because was that a red lace pattern she just saw claw its way along Kara's veins?

She calmly watches Kara, alluring swagger in her step as she sways over towards them with a smirk, eyes locked onto their about-to-be-released prisoner, Max.

"Maxie! Long time, no see. You don't call, you don't write, you don't attempt to kill me anymore. A girl gets lonely, Maxie, I thought we had a thing…"

Alex barely represses her shudder as she watches Kara get far too close to a pleased looking Maxwell Lord, Kara's pointer finger running down his chest and far lower than Alex ever wants to see her baby sister go.

But Kara's not herself, and the entire DEO is suddenly on edge.

Alex knows the weapon they used last time to neutralize this particular threat is locked away in the armory, and if anyone were to make a move, Kara would raze the facility to the ground before any of them could even blink.

So Alex's mind hurriedly formulates a plan, a stupid one admittedly, and pipes up, "Mr. Lord here came to us for assistance; he suspects CADMUS to be behind an attack on his labs. Though seeing as we can't account for anything missing, it seems he's made a trip for naught."

To his credit, Max Lord – ever the survivalist – recognizes that something's not quite right with Supergirl because he smiles graciously and nods along to Alex's words; he's clearly made the connection between Supergirl's current mood and the break-in into his facilities.

Red Kryptonite.

"That's a shame; I was looking forward to playing with Maxie."

"Oh, Supergirl, so was I. Perhaps though we can have dinner?"

"Or we can just meet up for a quick lay and be done with it. Say, tonight at midnight until… tomorrow morning? That should give you enough time to make sure your bed is reinforced."

Alex is sure she vomits a little in her mouth as she watches Kara, fist painfully in Max's hair and tilting his head roughly back, lean in and lay a decidedly filthy, wet, open-mouthed kiss against Max's throat.

Alex makes a mental note to wring Max Lord's neck personally when his laugh rings around the stunned silence wrapping around the DEO as he walks away, only stumbling slightly from Kara's unnecessarily rough shove away and not once losing his obnoxious air of amusement.

Alex has to remember to remain calm even as the rest of the DEO is now on high alert, eyes on Kara as she turns and wanders away down the hallway, Alex forced to pick up her speed a little to keep up with Kara's long strides.

All she needs to do is successfully detain Kara without her catching on and then they can zap her back to herself.

"Kara, I think the Alura AI is missing some info, or has incorrect data, or maybe she's just glitching. Anyway, I need your help to fact check some stuff. Can you please come with me?"

Alex was too consumed with making sure they pass by J'onn's office so she can telepathically alert him to the danger to notice Kara's smirk, her eyes flashing a sinister blood red.

"Sure, Sis. Was there a virus or something?"

"I'm not sure. I think the last software update Winn did knocked something out of balance."

Alex curses her luck as Kara scans her hand and lets them into the AI room; J'onn wasn't in his office.

Now Alex is trapped, without backup, in a room with an unhinged Kryptonian with a planet's worth of baggage, and a deeply buried grudge against Alex that could turn deadly if she pushes the wrong buttons.

The door has barely closed behind them when Alex feels herself grabbed by the back of the collar and slammed into a wall, Kara's twisted laugh filling her ears as her breath is forcibly taken from her lungs, her body slumping painfully to the ground.

"Do you think I'm a moron, Alex?"

Alex feels herself get picked up by the hair and tossed across the room, straight through Alura's smiling specter.

"I am an alien from a planet millennia ahead of your world's primeval so-called science."

Kara's slowly stalking closer, though her silhouette is slightly blurred around the edges to Alex's pain-filled mind.

"I was set to be the youngest member of the science guild; do you really think I couldn't figure out your pathetic excuse to get me alone and ambush me?"

When Kara's boot connects with her ribs, and the crunch of broken bones fills the air, Alex bites into her bottom lip so fiercely her mouth fills with blood.

Her eyes are swimming, and she's dimly aware that she's not, in fact, dead. Which only means, even at her worst, Kara's holding back. Sure, she might have just beaten Alex to within an inch of her life, but she hasn't killed her.

"You're pathetic, Alexandra."

As Kara turns away, and Alex's vision darkens further – first around the edges before moving inwards – Alex's last thoughts are of how completely idiotic it was to lure Kara into a room only accessible with Kara's handprint as Kara seals her in.

And then, nothing.

* * *

Nobody dares cross paths with Kara as she strides back out towards the DEO balcony, smile serene and _humming_.

Her tone, outwardly casual, is lined with threat as she calls out over her shoulder that she has a, "lunch date with Lena. Nobody interrupt if you value your life."

Winn and Vasquez watch the dot that is supposed to be Kara get far enough before the main room of the DEO breaks out into chaos.

Vasquez is on her feet in a flash, and running to find J'onn, while Winn runs in the direction Kara came from to find Alex, terrified of what he might find.

In their frantic states, nobody remembers to call Lena and warn her.

* * *

Kara's flying towards L-Corp at a leisurely pace, ignoring the calls for help from below.

She's too busy with thoughts of all the sinful things she wants to do to Lena; of pushing her against her desk and making her beg; of pressing her into the wall so roughly that Jess, sitting outside, will have absolutely no doubt as to what's happening inside her boss's office; of making Lena scream her name out on the balcony so everyone can hear and see.

Thoughts of finally having what she's denied herself for months in the name of honor and chivalry.

Thoughts of finally _taking_ what she wants.

Her thoughts, however, come to a halt when she hears three heartbeats in Lena's office instead of the one she expects.

She's deciding on whether or not it's best to evict a business partner or two, or put on a show for them instead when she lands on the balcony – and interrupts what seems to be a CADMUS meeting.

Lena's already rushing towards her when the brute Cyborg Superman pulls her harshly back by the wrist and starts charging Supergirl himself.

He's fast, but he isn't fast enough that Supergirl may have missed the glowing green knife in Lena's hand.

The red lace flares to life with her growing rage, her eyes flashing red for far longer than ever before.

It takes her no effort at all; using Henshaw's own momentum against him, Supergirl grabs him by the collar and the back of his shirt, slamming him into the ground and splitting the balcony. She lifts off into a hover when a chunk of the concrete falls away, and she flings Henshaw over the remaining railing, her eyes never straying from Lena – whose eyes are full of fear at the excessive and callous display of strength.

Supergirl's voice is downright deadly, not even sparing Lillian Luthor a glance as she tells her to, "Leave. While I'm still allowing you to."

And Lillian – much like Max – is a survivalist; she calmly steps around her daughter, not even sparing Lena another glance, or even trying to save her as she gracefully glides out of the room, leaving Lena to face a corrupted Super.

"Supergirl-"

"I should have known you'd be just like the rest of them; another dirty, disgusting, _evil_ _**Luthor**_."

"What-? No! Supergirl, you're not-"

The slap across Lena's face crackles like thunder, and Lena falls to the ground with a breathless gasp.

"I _knew_ you'd betray me, you whore!"

"Supergirl, please- this isn't- what's-"

Stepping on Lena's hand that still loosely holds on to the Kryptonite knife, Kara's smirk twists into something abominable as she slowly but surely breaks Lena's fingers, relishing in the pained scream she elicits.

Bending down, Kara fists Lena's hair and lifts her high up off the ground, snarling.

"You're nothing more than a cheap knock-off of Lex Luthor. I should have killed you when I had the chance. But you know what they say; better late than never."

Lena, disoriented and in pain and so very terrified of Kara, barely has time to register the green spider webbing weaving into the red lace coursing just under Kara's skin before she feels a cold kind of pain settle into her belly.

"I've always wondered what Kryptonite would do to humans. I guess now's as good a time as any to find out."

And then Kara's hands are releasing her, and Lena's unceremoniously dropped onto the ground a few feet below with thud.

Lena can't even bring herself to cry out; the shock at how the day has turned out too great.

As she lays there, bleeding and broken, and watches Kara turn her hand over in front of her face in fascination, observes Lena's blood coating her fingers with a detached smile, Lena's dimly aware that Kara had aimed it so she wouldn't hit any vital organs, likely so she can watch Lena die a slow and painful death.

With tears rapidly building in her eyes, and a painful lump choking off her air, Lena keeps her eyes on the red lacing Kara's veins, and croaks out a hoarse and breathless, "I- forgive you, Supergirl…"

Kara's laugh is loud and disbelieving as her boot harshly nudges into a bare leg, "You _forgive_ me? For what, doing everyone a favor and ridding the world of a filthy Luthor? I don't need your _forgiveness_ ; I'm a _hero_."

And perhaps it's the wrong thing to do, but Lena's convinced she's about to die here anyway, so what does it matter if she angers the invincible alien standing overhead any more than she already has?

She smiles.

And whispers, weaker and slowly losing consciousness, "Y-yes, you cert-ainly are, Ka-kara. You're _my_ hero. Al-always."

And, Lena thinks, she sees a flash of shock momentarily push away the red haze clouding Kara's eyes before the staggering pain she's in overwhelms her.

The last thing Lena sees before the world darkens to nothing is a flash of red before Kara collapses beside her, and the last thing she hears is Kara's gasped breath as Lena's brain manages to push out a last, "I-I lo-ove yo-"

* * *

When she opens her eyes, Kara's vision is assaulted with red, and she chokes out a sob.

She wishes more than anything that someone had done something _more_ to her so she'd never have opened her eyes again, not after what she's done.

The red overhead is too much; she's had a lifetime's worth of the color to torment her, and she needs to get out of here, she needs to find Le-

She's strapped down.

She's strapped down to a metal table and powerlessly tugging on her restraints.

For one, self-hating moment, Kara wonders if she's finally been handed over to the government to get the punishment she deserves.

And then a familiar voice, a tired voice, _a voice in pain_ reaches her ears, though Alex doesn't cross into her line of sight.

"Red sunlamps and steel shackles. We didn't want to take any chances – not after everything."

And Kara's sobs are brutal, tearing her apart on the inside better than any red poison could.

It takes long moments before Alex shuffles into view, and Kara's head snaps away from her handy work; from Alex's bruised and stitched face, from her arm cradling her ribs.

From the tears barely held back in Alex's eyes.

From the blood still staining her fingers.

Blood that, Kara _knows_ , is coating her own fingers too.

Blood she had _relished_ having on her hand.

And when Alex's fingers, tentative though loving – _always loving, even in the face of this disaster_ – covers hers, Kara flinches away, her anguished sobs turning into bone-breaking howls of sorrow.

And Alex lets her get it out, though her fingers chase Kara's and hold on tight through it all.

And she waits her out – waits until Kara's misery has been contained back into her own shivering frame before pulling aside the curtain.

And Alex watches then, with weary eyes, as the fire under Kara's anguish and suffering is stoked, as her back-to-their-steel-blue eyes, full of tears and heartbreak, take in the machines and the weak-though-steady-pulse, take in the pale cheeks, mottled with purpling bruises, and the barely-there breaths of Lena Luthor.


End file.
